Cooling neutral particles in multimode cavities without spontaneous emission

We discuss a scheme to cool, trap and manipulate an ensemble of polarizable particles moving in the field of a multimode optical cavity via the correl ated dynamics of the field and the particle motion. Using a large detuning between the atoms and the field, spontaneous emission plays a negligible ro le in the dynamics and the cooling scheme only requires a sufficiently larg e optical dipole moment. Increasing the particle number slows down the cool ing process but it can be accelerated using an increasing number of field m odes with higher pump amplitudes. For the special case of a two mode ring c avity and assuming small deviations of the particle positions from the pote ntial minima, the frequencies and damping rates of the vibrational excitati on modes can be explicitly calculated. We find a rapid damping of the centr e-of-mass motion and relatively slow damping rates for the relative particl e oscillations. These predictions agree quite well with a quantum treatment of the atomic motion as used for the excitations of a non-interacting Bose gas (at T = 0) inside the cavity field. Due to the position-dependent mode coupling, the cooling process in a multimode configuration in general happ ens much faster than for a standing wave geometry. These analytical results are confirmed by N-particle simulations of the semiclassical equations and show even enhanced damping due to the anharmonicity of the full potential.